Sports megastore Decathlon has earned a solid reputation for delivering great value budget bikes under the B’Twin brand name – we named the Triban 500 SE our Budget Bike of the Year for 2014/15 and the Triban 540 our Sub-£1,000 Bike of the Year 2016-17. But there is more to the firm’s offering than that. As well as other versions of the Triban, the various setups of the B’Twin Ultra also cater for those looking for superior performance.
At the time of writing, Decathlon road bike prices range from £249 for the Triban 100, up to £3,499 for the top-of-the range Ultra 940 CF Team Edition.
Seemingly overlapping price ranges for different-named bikes can make life confusing, particularly when you throw in the occasional whopping great discount for an end-of-the-line model. Fortunately, Decathlon usually (but not always) abides by the time-honoured naming convention of ‘bigger number, better bike,’ so this can give you a general idea of the hierarchy.
In simple terms:
- The Triban is the entry-level model and Decathlon’s best-selling bike by a country mile
- An aluminium version of the Ultra has replaced the Alur a notch above that
- The Ultra is the Grand Tour all-rounder or Ardennes classics specialist – designed to be smooth, light and responsive
The Triban range comprises the 100, 500, 520, and 540, all with aluminium frames.
The entry-level model in B’Twin’s road range, the Triban 100 is built around a 6061 aluminium frame with a geometry that’s designed for comfort. The top tube is shorter than that of a traditional road bike and the head tube is longer so the ride position is a little more relaxed, putting less strain on your back and neck. A sloping top tube reduces the standover height.
The fork is high tensile steel rather than lighter weight aluminium or carbon, although you have to expect that on a bike of this price.
The Triban 100 comes with a single chainring and a 7-speed Shimano cassette. You don’t get the range of gears that you do with the more expensive models in the Triban range but the Shimano A050 rocker shifter mounted next to the stem provides easy, reliable changes.
The B-Twin 700 wheels are fitted with 32mm-wide tyres that are designed to provide plenty of comfort both on road and on smoother paths, and you get eyelets for fitting mudguards and a rear rack which could come in handy if you want to use the bike for commuting.
Buy if: You’re looking for a no-frills entry-level road bike.
The Triban 500 is built around the same 6016 aluminium frame as the Triban 100 (above) but it’s a very different bike with a carbon-legged fork and a triple chainset. The choice of three different chainrings (50/39/30-tooth) and an 8-speed (12-25-tooth) cassette gives you a wide spread of gears including some low options for getting up the climbs.
Like most higher-level bikes, the Triban 500 comes with combined brake lever and gear shifter units – in this case they’re from MicroShift. It’s a different shift system from more popular Shimano, but it works just fine.
The tyres are 25mm wide, which has become the norm for road bikes over the past few years, and you get the relevant eyelets for fitting mudguards and a rack.
The Triban 500 has lighter wheels than the Triban 500 SE (above).
B’Twin also offers a Triban 500 with a flat handlebar for £260. You still get a triple chainset and a 7-speed cassette but the spec is quite different.
Buy if: You’re after a versatile aluminium road bike that'll get you up the climbs.
The B’Twin Triban 520 was our Bargain Bike of the Year 2015-16.
“If you're starting out in road cycling and you've got less than £500 to spend, then this bike is one you should be chucking your hard-earned cash at,” we said in our review. “It's not just a good bike for the money, it's a good bike, full stop.”
The Triban 520 is a fun bike to ride. The alloy frame is lighter than the 500's. That frame and the carbon-bladed fork are well made and finished, and they give the bike an assured feel.
The bike's not as stiff as a carbon race frame, and you can eke out some derailleur rub in the bottom bracket area if you put the hammer down, but it's well within the acceptable range. The fork has a straight-through 1 1/8in steerer but the Triban doesn't want for stiffness up front, it tracks very well.
Shimano's fifth-tier Sora groupset takes care of the shifting, and as usual it was a trouble-free experience. You get much of the performance of more expensive groupsets – and proper Dual Control shifters – at a much reduced price.
Reviewer Dave tried everything from commuting to racing on the Triban 520 and it acquitted itself as well as bikes costing twice as much. It's a steal. This is a brilliant bike for the money, and B'Twin tell us they've upgraded the brakes since we reviewed it, which should deal with the biggest flaw we found.
B’Twin also offers the Triban 520 with a flat handlebar for £429. That version also comes with a Shimano Sora groupset although the chainset is downgraded to a Prowheel Ounce instead.
Buy if: You’re looking for a road bike that delivers a great ride and stunning versatility for an exceptional price.
The B’Twin Triban 540 was the road.cc Sub-£1,000 Bike of the Year 2016-17.
When we reviewed it, we said that it was a real joy to ride with an incredible spec for its price.
With a triple-butted aluminium frame (which is shares with the Triban 520) it feels fast, comfortable and responsive without much of the buzzy feeling you sometimes get from aluminium. The carbon-legged fork also effectively absorbs bumps in the road. There's little to complain about, comfort-wise. It has front and rear rack and mudguard mounts, so you can load it up for weekend tours or all-year-round commuting.
The Triban 540 is a pleasure to pilot, whether you're on smooth new tarmac, decaying and rough road surfaces or even over cobbles.
B’Twin hasn't gone down the route of oversizing the bottom bracket junction, but the frame doesn't lack anything because of it. The slim seatstays offer some flex, and while steering feels easy and relaxed when you're cruising, it's responsive when you need it to be.
The groupset is Shimano’s mid-level 105, which is excellent value on a bike of this price, although the chainset is Shimano RS500 with 52/36-tooth chainrings. Decathlon's own-brand dual-pivot rim brakes (made by Tektro) perform well, including for sudden stops – no complaints there.
The Mavic Aksium One wheels are fitted with 25mm Hutchinson Equinox tyres which roll well and offer a decent amount of grip. When they do wear out, the frame has enough clearance for 32mm tyres (without mudguards) – which would increase comfort further.
Overall, this is a great buy for those new to road bikes and those looking to their next cycling challenge, and Decathlon offers a lifetime warranty on the frame, fork, stem and handlebar.
Buy if: You’re looking for a capable aluminium road bike with a strong spec.
B’Twin Ultra AF
The Ultra AF is an aluminium framed bike with a carbon fork.
The Ultra 900 uses the same 6061 aluminium frame as the Ultra 920 and the Ultra 940 AF Di2 (below), and also the same one that was at the heart of the Ultra 700 AF (no longer available) that we reviewed last year on road.cc.
The frame is triple butted and comes with internal cable routing and direct mount brakes, the rear one tucked underneath the chainstays.
The geometry is fairly sporty – firmly in fast-endurance kind of territory. That means you can ride the B’Twin at a real old lick without having to scrunch yourself up into a ball to get into an aero position. It's a quick bike too, with very impressive stiffness for an entry-level alloy frame.
B’Twin hasn't gone down the route of oversizing the bottom bracket junction, keeping with a standard sized press-fit unit, but the frame doesn't seem to lack anything because of it. Really stamping on the pedals on a steep climb or in full-on sprint mode will find the smallest hint of flex at the BB, but we are talking minor amounts here and not something you'll pick up on unless you're really looking for it.
B’Twin has oversized the front end, though, using the now pretty standard tapered head tube – 1 1/8in at the top flaring to 1 1/4in at the bottom. It's all about adding stiffness by increasing the cross sectional area.
As a result, the handling on the Ultra AF is direct with a positive feel to it, something it manages without being overly twitchy at the front end. The steering has a neutral feel while still being responsive, which is ideal on a bike that's likely to be bought by those getting into the sport.
For those with a bit more experience, or riders who just like a bit of an adrenaline hit, the Ultra 900 Aluminium maintains that positivity as the speed increase. It may not have the precision of some thoroughbred race bikes but it's not going to be found wanting until you are absolutely pushing it to its limits.
Comfort is often cited as a reason to avoid aluminium alloy bikes and it's true, the Ultra AF can feel a little on the harsh side at times, though it is still far from uncomfortable. It's just not as refined as some, but still manages to tame road buzz to a minimum.
The Ultra 900 Aluminium is built up with a very good Shimano 105 groupset and Mavic Aksium wheels, making it excellent value.
Buy if: You’d like a sporty aluminium road bike in an excellent build for the price.
The Ultra 920 AF is built around the same 6061 aluminium frame (1,400g claimed weight) and carbon/aluminium fork (550g claimed weight) as the Ultra 900 AF, though the rear brake has moved from the chainstays up to the seatstays..
The difference is in the choice of components, the Ultra 920 AF coming with the new Shimano R8000 Ultegra groupset – a level higher than the Ultra 920 AF’s 105 – Mavic Cosmic Elite wheels and a very good Fizik Arione saddle.
Buy if: You’d like a road bike that offers an exciting ride and excellent value.
The Ultra 500 AF GF is an aluminium framed (hence the AF) bike designed for gran fondos (hence the GF) and other endurance ventures. It's one of a pair of bike with disc brakes, in this case cable discs to keep the price under control.
The frame geometry is a bit shorter and taller than that of the Ultra AF aluminium bikes (above) so you get a more relaxed riding position. The GF model also has a more sloped top tube for a lower standover height.
The frame, which has a claimed weight of 1,470g, has a tapered head tube (1 1/8in upper bearing, 1 1/2in lower bearing) and, like the fork (a claimed 430g), it’s thru axle (with closed rather than open-ended dropouts) and takes Flat Mount disc brakes.
Buy if: You want a disc-braked endurance bike under the Cycle To Work Scheme threshold.
The Ultra 520 AF GF is the upmarket version of the Ultra AF GF platform and currently the only road bike in the B’Twin lineup to come with hydraulic disc brakes
The Ultra 520 AF GF is built up with a full SRAM Rival HRD groupset, Mavic Ksyrium Disc wheels, Deda bars and stem and a Fizik saddle. It's a very solid spec for the money.
Buy if: You want an aluminium endurance bike with the all-weather performance of hydraulic disc brakes.
B’Twin Ultra CF
The Ultra CF is a carbon-fibre road bike which is available with both a variety of mechanical gears; an electronic version if expected later in 2018. It is a stiff, light performance bike with internal cabling, built around B'Twin's Ultra Evo Dynamic carbon fibre frame, which Decathlon claims the weighs just 850g in a size Medium, and the fork 320g. Those are impressive numbers for the frame of bikes in this price range.
The most eye-catching part of the carbon-fibre frame is the large and angular down tube. The head tube is tapered, the bottom bracket is Press Fit 86, and the carbon seatpost is held in place by an integrated wedge-style clamp.
The Ultra 900 Carbon is made to a race geometry and is built up with Shimano’s mid-level 11-speed 105 groupset. 105 is slightly heavier than Shimano Dura-Ace and Ultegra but not by much, and the level of performance is excellent.
Mavic’s Aksium One wheels offer very good value too.
B’Twin provides branded components right across the board with a handlebar and stem from Deda and a Fizik Antares saddle.
Buy if: You'd like a carbon-fibre road bike with a solid, reliable groupset.
When we first rode B’Twin’s Ultra CF we described it as “a performance-orientated road bike that really impresses in combining frame rigidity with a comfortable ride”.
The design has changed a little since then but the Ultra 920 is still focused on fast road riding: racing, if that’s your thing, sportives maybe, or just ragging it around the roads with your mates. The geometry is race-orientated – head-down and stretched rather than sit-up-and-beg, which is entirely appropriate for a bike like this.
Rather than the Shimano 105-based spec of the Ultra 900 CF, the Ultra 920 Potenza is decked out in Potenza components, Campagnolo's answer to Shimano Ultegra.
The wheels are from the Campagnolo lineup too: Zondas with aluminium rims. You’re getting excellent value here.
Buy if: You want a stiff and light performance-orientated bike with a great spec for the cash.
Originally £2,300, the Ultra 920 CF Ultegra has seen a substantial price drop since we last updated this guide and is now a very good deal, especially given its high-quality finishing kit (Deda bar and stem, Fizik saddle) and Mavic Cosmic Pro Carbon wheels.
The Ultegra R8000 groupset is a solid performer, and Decathlon has gone for a performance-orientated set-up with a 52/36 chainset and 11-28 cassette.
Buy if: You want a light, fast bike at a very sensible price
For the flagship model in the range, B'Twin hangs a compete Dura-Ace groupset on the Ultra carbon frame and throws in a pair of Zipp 303 wheels, a Deda carbon handlebar and Vittoria's renowned Corsa Graphene tyres. Three and a half grand isn't cheap by anyone's standards, but it's still excellent value for money.
Buy if: You want Dura-Ace and Zipp wheels without too outrageous a price tag.
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